This invention relates generally to orthodontic appliances for expanding the upper, or maxillary, jaw of a person. And more specifically the invention pertains to an expander connected directly to the palate of a person, without using bands or crowns upon teeth, thus adjusting the shape of the maxillary jaw while improving the appearance of a person's mouth and teeth through usage of the present invention.
Over a long time, orthodontists labored towards correcting tooth positions and related jaw conditions to remedy various conditions afflicting patients. Such conditions include overbite and underbite, improper chewing, dental speech impediments, hygiene, and appearance. As a further complication to patients, the lower jaw, or mandible, may grow during a person's lifetime and affect the alignment of teeth in both jaws. To begin, each tooth can be rotated and translated into a new location or orientation as it secures to the jaw with a periodontal ligament. Though extremely strong, the periodontal ligament stretches like other ligaments as a tooth moves. Generally, a tooth is moved in increments from an initial to a final position, often along a standard arc like shape.
Orthodontists use many devices and therapies to move teeth while remedying conditions. Common braces have a wire secured to brackets or bands upon teeth. The brackets were once adhered to the exterior face of a tooth but presently the demands of patients call for securing the brackets to the interior face of a tooth. A wire then is placed upon the bracket and secured by small diameter elastic bands. The arcuate shape of the wire corresponds to the desired position of teeth. Wires have sizes that increase incrementally in diameter and hence rigidity so changing wires from smaller to larger diameters over time generally moves the teeth into a desired position. Each tooth attains its desired position according to the orthodontic treatment plan through the rigidity of the wire. Brackets generally are used in positions rearward from the incisors.
For following an orthodontic plan, an orthodontist may have to create additional space along the jaw to ease tooth movement. Moving teeth rearward opens the space for guiding teeth towards their final positions. An orthodontist applies bands to the molars and if needed, teeth towards the front of the mouth. A band generally adheres to and surrounds a tooth. A fitting generally upon the exterior of a band secures the end of a wire used to establish a desired arc for the teeth on a jaw. Bands also have sockets, generally horizontal, upon the exterior that cooperate with headgear having interior rods received into the sockets upon the molars and an integral outer bow. The outer bow connects to an adjustable strap around the patient's neck. The strap provides a rearward force into the bow and the interior rods to move the molars rearward. This action opens additional space for other teeth that then move to desired positions upon the jaw.
Beyond moving individual teeth along a jaw, an orthodontist may open space for teeth where a jaw has a too narrow shape. A jaw widens while gently pushing the molars outwardly. As above, molars were moved outwards using bands connected to a threaded jack. A coaxial rod connected to a moving bar, or wing for a jack that a threaded cylinder with keyholes for adjusting the length of the rod. A patient performed these adjustments by inserting a key into the keyholes on a prescribed schedule and turning the cylinder a certain amount of rotation. Turning the cylinder urged the wings outwards and the jack against the molars to expand the jaw, most often the maxillary jaw.
Lately, the orthodontic community and manufacturers have developed mouth pieces that fit over teeth while guiding them into new positions. A translucent polymer material forms the mouthpieces as they fit over the teeth, as found initially by the orthodontist, without the bands, wires, and brackets of the prior art. Manufacturers, such as Invisalign® among others, provide mouth pieces, generally modeled in three dimensions by proprietary software for locating teeth in proper positions. The mouth pieces, akin to prior art wires, gently move teeth incrementally over time. The mouth pieces can be worn during the daytime without any perception by people other than a patient. An orthodontist prescribes the mouth pieces in stages which then guide the amount of tooth movement. Friction between the mouth piece and the surface of the teeth generally holds the mouth piece in place. Aligning teeth well along an arc, the mouth pieces do not yet provide expansive lateral forces to widen a jaw or alternatively to contract a jaw.
Attempting to provide expansive lateral forces, the prior art merges a mouthpiece with an expansion device. Vacuuming forming connects an expansion device to a separately manufactured mouthpiece. Further, an expansion device may join to a mouthpiece from pelletized plastic or acrylic placed irregularly upon the surface of a union of the expansion device and a mouthpiece. The junction and the pellets of plastic are then heated or chemically treated to bond the expansion device to the mouthpiece.